Treating early psychosis: who, what, and when?

Prospective study of cannabis use in adolescents at clinical high risk for psychosis: impact on conversion to psychosis and functional outcome

BACKGROUND

Clinical and epidemiological studies suggest an association between cannabis use and psychosis but this relationship remains controversial.

METHOD

Clinical high-risk (CHR) subjects (age 12-22 years) with attenuated positive symptoms of psychosis (CHR+, n=101) were compared to healthy controls (HC, n=59) on rates of substance use, including cannabis. CHR+ subjects with and without lifetime cannabis use (and abuse) were compared on prodromal symptoms and social/role functioning at baseline. Participants were followed an average of 2.97 years to determine psychosis conversion status and functional outcome.

RESULTS

At baseline, CHR+ subjects had significantly higher rates of lifetime cannabis use than HC. CHR+ lifetime cannabis users (n=35) were older (p=0.015, trend), more likely to be Caucasian (p=0.002), less socially anhedonic (p<0.001) and had higher Global Functioning: Social (GF:Social) scores (p<0.001) than non-users (n=61). CHR+ cannabis users continued to have higher social functioning than non-users at follow-up (p<0.001) but showed no differences in role functioning. A small sample of CHR+ cannabis abusers (n=10) showed similar results in that abusers were older (p=0.008), less socially anhedonic (p=0.017, trend) and had higher baseline GF:Social scores (p=0.006) than non-abusers. Logistic regression analyses revealed that conversion to psychosis in CHR+ subjects (n=15) was not related to lifetime cannabis use or abuse.

CONCLUSIONS

The current data do not indicate that low to moderate lifetime cannabis use is a major contributor to psychosis or poor social and role functioning in clinical high-risk youth with attenuated positive symptoms of psychosis.

Is early intervention in psychosis effective?

Aims – Psychosis is a traumatic experience for both sufferers and their families. The morbidity and mortality associated with psychosis may be improved by an assertive, specialised, multidisciplinary approach to care, provided at the earliest opportunity. Early Intervention in Psychosis (EIP) uses such approach to improve the individual's short and long-term symptomatic and functional outcome, as well as quality of life. However, there is still controversy about whether this type of intervention is effective enough to justify its associated costs. Methods – We reviewed evidence from the literature on EIP for schizophrenia spectrum and non-affective psychoses, with particular attention to evidence on its effectiveness in reducing the duration of untreated symptoms, preventing relapses and reducing admission rates, reducing suicide rates, and reducing treatment costs. Results – There is preliminary evidence that EIP may be effective in delaying transition to psychosis, reducing DUP, preventing relapses, reducing admission and suicidal rates, and reducing treatment costs. Discussion – EIP remains a stimulating multidisciplinary approach to psychosis and a demanding commitment for mental health professionals and service developers.

Declaration of Interest: None.

Young rural people at risk for schizophrenia: time for mental health services to translate research evidence into best practice of care

Early intervention into prodromal schizophrenia has shown promise, but controversy continues regarding the ethical acceptability of identifying a group of 'ultra high risk' individuals of whom only 30 to 50% will develop a psychotic disorder. With well developed early intervention services this group faces the possibility of being labelled as 'pre-psychotic', a condition for which the well known stigma associated with the diagnosis of schizophrenia or bipolar disorder is likely to be associated. In addition, the use of potent antipsychotic and other medications (albeit usually at lower doses than those used for those with manifest psychosis) mandates consideration of the risks associated with their use and neurological and metabolic side effects. The potential for iatrogenic morbidity in the 'false positive' group must be weighed against the need of the 'true positives' identified through screening and assessment. Current evidence for the concept of 'at-risk mental state' was reviewed within a neurodevelopmental framework, including emerging data on the effectiveness of early intervention for the purpose of providing recommendations for community mental health services. The review suggests that different treatment strategies may be appropriate depending on the clinical stage of the condition as long as the benefits of intervention outweigh its risk burden. It further suggests that the severity of psychoses and the evidence of its early onset in utero and its acceleration in adolescence positions 'ultra high risk' intervention as a core model for early intervention for young people by teasing apart the symptomatic components of the 'prepsychotic state' and ensuring the population is reaching targeted mental health services for screening. The model is not restricted to the delivery of intervention for 'pre-psychotic' young people but is applicable for targeted programmes for a number of clinical groups considered at 'ultra high risk'. However, only further research in naturalistic populations embedded in clinical practice and ideally conducted in partnership of mental health services with academic research institutions will help clarify potential risks of early identification and intervention and assist in updating and making more explicit the clinical guidelines services will use in approaching those in the 'ultra high risk' group.

Prenatal exposure to infection: a primary mechanism for abnormal dopaminergic development in schizophrenia

RATIONALE

Prenatal exposure to infection is a notable environmental risk factor in the development of schizophrenia. One prevalent hypothesis suggests that infection-induced disruption of early prenatal brain development predisposes the organism to long-lasting structural and functional brain abnormalities. Many of the prenatal infection-induced functional brain abnormalities appear to be closely associated with imbalances in the mesocorticolimbic dopamine system in adult life, suggesting that disruption of functional and structural dopaminergic development may be at the core of the developmental neuropathology associated with psychosis-related abnormalities induced by prenatal exposure to infection.

OBJECTIVES

In this review, we integrate recent findings derived from experimental models in animals with parallel research in humans which supports this hypothesis. We thereby highlight the developmental perspective of abnormal DA functions following in-utero exposure to infection in relation to the developmental and maturational mechanisms potentially involved in schizophrenia.

RESULTS

Experimental investigations show that early prenatal immune challenge can lead to the emergence of early structural and functional alterations in the mesocorticolimbic DA system, long before the onset of the full spectrum of psychosis-associated behavioral and cognitive abnormalities in adulthood.

CONCLUSIONS

Dopaminergic mal-development in general, and following prenatal immune activation in particular, may represent a primary etiopathological mechanism in the development of schizophrenia and related disorders. This hypothesis differs from the view that dopaminergic abnormalities in schizophrenia may be secondary to abnormalities in other brain structures and/or neurotransmitter systems. The existence of primary dopaminergic mechanisms may have important implications for the identification and early treatment of individuals prodromally symptomatic for schizophrenia.

Measuring Memory-Prediction Errors and their Consequences in Youth at Risk for Schizophrenia

The largely consistent columnar circuitry observed throughout the cortex may serve to continuously predict bottom-up activation based on invariant memories. This “memory-prediction” function is essential to efficient and accurate perception. Many of the defined cognitive deficits associated with schizophrenia suggest a breakdown of memory-prediction function. As deficits in memory-prediction function are proposed to lie more proximal to the biological causes of schizophrenia than deficits in standard cognitive constructs, tests that more directly probe memory-prediction function may be especially sensitive predictors of conversion in individuals at high-risk for schizophrenia. In this article, we review the conceptual basis for this hypothesis, and outline how it may be tested with specific cognitive paradigms. The accurate identification of cognitive processes that precede the onset of psychosis will not only be useful for clinicians to predict which young people are at greatest risk for schizophrenia, but will also help determine the neurobiology of psychosis onset, thus leading to new and effective treatments for preventing schizophrenia and other psychoses. Key words: Cognition, Cortical circuitry, Psychosis, Schizophrenia, Ultra high-risk

Prospective outcome of early intervention for individuals at ultra-high-risk for psychosis

AIM

Based on previous reports of second-generation antipsychotic agents having a beneficial effect on prodromal symptoms, we investigated the effectiveness and tolerability of atypical antipsychotic therapies in individuals at high risk for developing psychosis.

METHODS

We examined prodromal symptoms and functioning in individuals at ultra-high-risk for psychosis using an uncontrolled prospective design with pre- and post-treatment measures.

RESULTS

Of the 27 subjects taking antipsychotics during the study period, 15 took part in at least one follow-up assessment. Overall Comprehensive Assessment of At-Risk Mental States scores significantly improved at the last evaluation point, with a medium-size effect of Cohen's d = 0.54 (95% confidence interval, -0.02 to 1.08) (mean follow-up period = 8.8; SD = 8.3 months). Depression and anxiety symptoms were markedly reduced, and global and social functioning also significantly improved. Of the 27 subjects, two (7.4%) converted to psychosis and 16 (59.3%) experienced at least one treatment-emergent adverse event, but no subjects exhibited serious adverse events.

CONCLUSIONS

The results of this study support treating high-risk individuals with antipsychotics to reduce prodromal symptoms with adequate safety.

Early intervention in psychosis: concepts, evidence and future directions

The rise of the early intervention paradigm in psychotic disorders represents a maturing of the therapeutic approach in psychiatry, as it embraces practical preventive strategies which are firmly established in mainstream health care. Early intervention means better access and systematic early delivery of existing and incremental improvements in knowledge rather than necessarily requiring dramatic and elusive breakthroughs. A clinical staging model has proven useful and may have wider utility in psychiatry. The earliest clinical stages of psychotic disorder are non-specific and multidimensional and overlap phenotypically with the initial stages of other disorders. This implies that treatment should proceed in a stepwise fashion depending upon safety, response and progression. Withholding treatment until severe and less reversible symptomatic and functional impairment have become entrenched represents a failure of care. While early intervention in psychosis has developed strongly in recent years, many countries have made no progress at all, and others have achieved only sparse coverage. The reform process has been substantially evidence-based, arguably more so than other system reforms in mental health. However, while evidence is necessary, it is insufficient. It is also a by-product as well as a catalyst of reform. In early psychosis, we have also seen the evidence-based paradigm misused to frustrate overdue reform. Mental disorders are the chronic diseases of the young, with their onset and maximum impact in late adolescence and early adult life. A broader focus for early intervention would solve many of the second order issues raised by the early psychosis reform process, such as diagnostic uncertainty despite a clear-cut need for care, stigma and engagement, and should be more effective in mobilizing community support. Early intervention represents a vital and challenging project for early adopters in global psychiatry to consider.

[Adolescent psychosis, can neuroscience improve prediction?]

Developments in the field of neuroscience have created a high level of interest in the subject of adolescent psychosis, particularly in relation to prediction and prevention. As the medical practice of adolescent psychosis and its treatment is characterised by a heterogeneity which is both symptomatic and evolutive, the somewhat poor prognosis of chronic development justifies the research performed: apparent indicators of schizophrenic disorders on the one hand and specific endophenotypes on the other are becoming increasingly important. The significant progresses made on the human genome show that the genetic predetermination in current psychiatric pathologies is complex and subject to moderating effects and there is therefore significant potential for nature-nurture interactions (between the environment and the genes). The road to be followed in researching the phenotypic expression of a psychosis gene is long and winding and is susceptible to many external influences at various levels with different effects. Neurobiological, neurophysiological, neuropsychological and neuroanatomical studies help to identify endophenotypes, which allow researchers to create identifying "markers" along this winding road. The endophenotypes could make it possible to redefine the nosological categories and enhance understanding of the physiopathology of schizophrenia. In a predictive approach, large-scale retrospective and prospective studies make it possible to identify risk factors, which are compatible with the neurodevelopmental hypothesis of schizophrenia. However, the predictive value of such markers or risk indicators is not yet sufficiently developed to offer a reliable early-detection method or possible schizophrenia prevention measures. Nonetheless, new developments show promise against the background of a possible future nosographic revolution, based on a paradigm shift. It is perhaps on the basis of homogeneous endophenotypes in particular that we will be able to understand what protects against, or indeed can trigger, psychosis irrespective of the clinical expression or attempts to isolate the common genetic and biological bases according to homogeneous clinical characteristics, which have to date, proved unsuccessful.

The treatment of schizophrenia: from premorbid manifestations to the first episode of psychosis

To achieve the best therapeutic results in schizophrenia--like most other disorders--primary prevention is preferable to early and prompt treatment, which, in turn, is preferable to treatment of chronically established illness. Unfortunately, there currently exist no accurate markers that can provide information regarding the future course of illness and guide treatment in asymptomatic or mildly symptomatic individuals. Therefore, most treatment efforts are currently focused on patients who have already experienced their first psychotic episode. This paper reviews the efforts to identify accurate markers heralding psychotic illness, as well as treatment considerations in the early phase of the disease.

The treatment of schizophrenia: from premorbid manifestations to the first episode of psychosis

To achieve the best therapeutic results in schizophrenia--like most other disorders--primary prevention is preferable to early and prompt treatment, which, in turn, is preferable to treatment of chronically established illness. Unfortunately, there currently exist no accurate markers that can provide information regarding the future course of illness and guide treatment in asymptomatic or mildly symptomatic individuals. Therefore, most treatment efforts are currently focused on patients who have already experienced their first psychotic episode. This paper reviews the efforts to identify accurate markers heralding psychotic illness, as well as treatment considerations in the early phase of the disease.